The reaction mechanisms by which several surfactants (notably sodium dodecyl sulfate, lithium 3,5-diiodosalicylate, taurocholic acid, and cetyltrimethylammonium bromide) solubilize human erythrocyte membranes will be determined. The principal technique used will be a kinetic one: The rate of solubilization will be determined from decreasing intensity of white light scattered by suspended membranes in a stopped-flow cuvette. These kinetic studies will be conducted over a broad range of temperatures, concentrations, and supporting electrolyte compositions to facilitate deduction of solubilizing mechanisms from activation parameters. Equilibrium dialysis experiments will be used to identify the mechanism of solvent-membrane binding. Fragment sizes and shapes will be deduced from static light scattering, viscosity, and ultracentrifugation studies. The overall objective will be the discovery of membrane solvents that discriminate more precisely between lipid, protein, and other membrane components than can presently used surfactants.